How do you pronounce st? This doesn't feel natural.
–
KobiAug 16 '10 at 8:45

2

I've noticed that speakers of Tagalog, for instance, seem to have difficulty saying words beginning with an S consonant blend, preferring to say estore or estudent.
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moiociAug 24 '10 at 14:03

2

moioci: I believe people around the world also do that. Since there is no word starting with s followed by consonant in Portuguese, people tend to think and speak like /ɪstɔːr/ instead of /stɔːr/
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Denilson SáNov 17 '10 at 23:56

3 Answers
3

Always use an for words which sound like they start with a vowel, and always use a for words which sound like they start with a consonant. The rules for h are more complex, and it can be ok to use either.

The usage of the indefinite article preceding h are discussed here. In particular, look at nohat's response.

As for student and store, they should always be preceded with a and never with an, because they both start with the consonant /s/ when spoken.